You will need to be invited to join Depop Payments currently and once you have been invited, you will be able to signup from:
Settings > Preferences > Depop Payments.
To signup you will need to go through Stripe to add some personal information including your bank account information and a form of ID when signing up. The information required differs by country and whether verification checks have been successful but you must be over 18 to have a Stripe account. If you are under 18, you will simply need to provide the ID of a parent or guardian instead.
Our payment processing partner Stripe may require additional information to verify your identity. We will refer you to a secure Stripe form to input these details. You Stripe account is also where your balance is kept and your Payouts are organised!